Producing High Quality Dry Hay

Prepared by Glenn Friesen, MAFRI Forage Specialist (BDS)

The Manitoba spring of 2010 began early with great promise, setting up for another productive year. As the season progresses, it is important to be ready to get your hay harvested at a level of quality your livestock need. Indeed, in years like this, the old adage, “make hay when the sun shines,” seems especially appropriate; however, may not be possible for some without causing too much stand damage. The unique balance of harvesting the hay during between the rains and minimizing stand damage in saturated soils may be a tough one for many this summer. For some producers, choosing to harvest their forage as silage bales (baleage) might be a better option than trying to get dry hay off the ground.

The primary goal in forage production is to preserve the quality until it can be fed. Harvest losses will often derail your plan for top quality forage. Losses can range from 10% for grass hay to as high as 35% for legumes, but these can be avoided by understanding where they commonly occur. Following are a few of the common loss sources during dry hay production and how to avoid them.

Pre-Baling Operations

Conditioning – Freshly cut hay is typically 80% moisture, and must lose about 6,000 lbs per acre of water for each ton of hay to reach 20% moisture. Conditioning can speed drying by opening the waxy cuticle layer surrounding the stem and allowing moisture to evaporate faster. Be sure your conditioner is adjusted correctly to maintain adequate roll pressure uniformly along the entire roll length. Apply sufficient roll pressure to the hay to cause a noticeable breaking of the stem skin, but not so much pressure that leaves are broken off. Proper adjustment of rollers can keep dry matter losses down to 1% to 3%.

However, conditioning slows cutting and requires much more horsepower and energy than raking. One should consider not conditioning, and rather cut with a wide swath (minimum of 70% the cutting width), increasing the speed of travel (up to 20-28 mph) and plan on raking the swath after a few days of drying. The result is typically similar time spent haying while using less energy and putting up higher quality hay. If conditioning is used, raking should take place within 24-48 hours after harvest.

Raking - Raking is typically done to put two or more windrows into one. However, more leaf loss can be caused by raking hay than by any other harvest operation when done too late. Avoid raking legumes when the forage moisture is less than 35 to 40%. If the rake is PTO driven, synchronize field speed and PTO speed to provide a gentle lifting and turning action. This will avoid aggressive handling of the forage and excessive leaf loss.

To form bales of consistent density and shape, make windrows uniform in width and uniform in the amount of hay contained. Field loss occurs as a bale turns within the round bale chamber, so don’t create unnecessary bale chamber loss by running the baler when there is no hay feeding into the chamber.

Wheel rakes are the most common type of rake on the Prairies and should be adjusted properly to avoid the high ash content in the hay. The height should be set just above the ground level. Paralell bar rakes can leave the forage “beat up” if travelling too fast – they should not be used for producing dry hay – rather only silage hay.

Tedding - Tedding fluffs, spreads or moves the windrow of hay, but should be done when the hay is still moist (at least 40% moisture) to reduce leaf loss, especially on legume hay stand. Some tedders simply shift the windrow several feet onto a dryer area while others spread out, invert and/or fluff the windrow. All these operations may improve drying, but the risk of leaf loss is high. This operation is better suited to grass hay fields, where dry matter losses are minimal. An alternative is to cut with a wide swath without a conditioner and rake prior to 40% moisture.

Macerators – Macerating crushes the stems and leaves of a plant, increasing the drying rate – occasionally resulting in the stems drying faster than the leaves. They are a useful option, however, they are an additional pass on the field (wheel traffic always reduces yield potential), slow and expensive.

Moisture Content – Hay moisture content is the largest single factor contributing to leaf loss. Hay baled above 15% has much less leaf loss.

When hay becomes too dry and brittle and losses become excessive, stop baling and resume in the evening or morning when the leaf moisture level increases. This dew-moistened hay can be baled at a slightly higher moisture level than when it was drying down because dew moisture in the hay is more easily released during curing than internal moisture.

The upper moisture level depends on the type of hay, density and size of bale, drying conditions after baling, and other factors. The upper limit for moisture for large round alfalfa bales is typically 18 to 20 percent. Hay baled much above 20 percent moisture will usually spoil unless chemical preservatives such as propionic acid are added to the hay. Effective hay preservatives will prevent excessive heating and mold growth when applied uniformly and at the correct rate. Wet bales are not only at risk for spoilage, but also fires; don’t take a chance if you’re uncertain. (see How Rain Affects the Quality of your Hay.)

The Baler

The baler pickup will typically create a 1 to 3% loss, but can be as high as 12%. Field speed, size of windrow, hay moisture content and mechanical condition of the pickup mechanism (broken and bent pickup teeth) accounts for this range.

Higher moisture content reduces pickup loss, so avoid baling when the hay is overly dry, especially legumes. Synchronize your ground speed to pickup speed to reduce this loss.

Another area of potential loss is the bale chamber. In general, bale chamber losses are normally two or three times higher in a large round baler than a rectangular baler. To minimize bale chamber losses, the moisture content should be as high as possible that will allow for safe storage (see safe storage details). The forage should be fed into the baler as fast as possible to minimize the number of turns within the bale chamber. A high feeding rate can be attained by using large windrows and high forward speeds. If the windrows are small or field speeds must be slow, reduce the PTO speed which results in fewer revolutions to form a bale.

Finally, when wrapping twine, do not rotate the bale more times than necessary to secure it. The fines, primarily leaves, which fall from the bale chamber during twine wrapping, are an indication of the bale chamber loss. These fines contain the highest level of nutrients, so minimizing these losses is important.

From the June 2010 edition of the CROPS E-NEWS (subscribe)